Valve control



W. RIEGER VALVE CONTROL Feb. 13, 1940.

Filed Jan. f1, 1938 5 Sheets-Sheet l ZZZz'ZZz elm fz ger lnvenfor:

BY I o I Q Azzomeys W. RIEGER VALVE CONTROL Feb. 13, 1940;

5 Sheets-Sheet 2 Filed Jan. 4 1958 Azzforners W. RIEGER 2,190,586

VALVE CONTROL Filed Jan. 4. 1938 5 Sheets-Sheet 3 v Inventor: l Zz'llzelm 1712 a 6 3 2 5 BY-' Azzomevs M M Feb. 13, 1940. w RjEGER 2,190,586

VALVE CONTROL Filed Jan. 4, 1938 5 Sheets-Sheet 5' Fz'gJU I 27a l as 74b 75 ijz 'zz {fl-e er hue/don i 15. hydraulically by a piston connectedto the valve Th regulating means is preferably formed by a Patented F b.l3,1940 t 2,190,586

UNITED} s'rnres rArE roFFicE -Wi1he1m Rieger, Kassel-Wilhelmshoh e Germany Application January 4, 1938, Serial N0.\183,3V95

. In Germany January 7, 1937 i 15 Claims. (01. Ell-+127) i 3 This invention is directed to a valve control valve by a direct mechanical connection to a, mechanism for internal combustion or for steam cam, and to drop thevalveunder the control of engines in which the movement of the valves is cam regulated hydraulic means.

cushioned by means oi a positively controlled, oil In general these objects of this invention are To? i cushion. obtained by providing a mechanical means for In the prior art, valve controls are of two the lifting of a valve stem, a means for placing general types, each of which acts hydraulically an oil cushion beneath thev stem, and means for I to lift the valve. In one type avalve lever rests lowering the valve raising mechanism before the on a cam shaft and is connected to an oil cylinvalve itself is dropped through the releasing of M 10 der for lifting the valve, and in which the oil the oil cushion beneath the valve .stem. This isallcwed to escape at a varying rate of speed valve cushion is then released in a positively so that the length t m f r h p nine and controlled manner so that the rate of fan of closing of the valve may be regulated. In a th alve an be regulated and the valve be Second yp the lifting of the Valve s performed cushioned against impact with the valve seat.) 7.

stem which cooperates with a second piston in i t l at d in a cylinder beneath the valve a l cylinderso that the 0 which is s l stem, said cylinder being connected to an oil to the cylinder in which the first piston is con- Supply ylinder d an 11 unease cylinder, An tained may be regulated, and thus the opening Ia'uxiliary'camshaft is provided in order to oper and the closineof t Valve may e date a piston located in the oil release cylinder, 20

In b of these types, the closmg mPVement and a piston in the oilsupply cylinder is operated of t Valve takes P 95 under the actlon a by cams placed on-both the main and auxiliary spring or'by the dropping of the valve under its cam Shafts; The, piston in the 011 supply 711 Own Welghti and only the pressure of the Valve der maintains the oil-in the valve stein cylinder stem against the on cvshion ccntrols the rate for a predetermined time, and when this piston 2 of emergence. of the 011 m i n9 releases the oil from the valve stem cylinder, the other reguiatlon of the escapmglofl being f oil passes to the oil release cylinder at a rate As the closing Valves inave velolclty determined by the movement of the piston in the when closmg 011 cushlon is not Suffictent .oilrelease cylinder, this movement being conusually to cushion the valves so as to prevent 1m trolled by cams on the auxiliary cam Shaft 30 pacts between the valve and the valve seat, and The means bv which these and other i consgquenfly i Operatic; t of this inventi on may be obtained are fully de- It is therefoie an ob ect of this invention to Scribedin followingspecification taken in, form a substantially'noiseless valve operating miect. h the acom an in drwin s e O 1013 v 1 Y E g 35: mechanism.

Another object of the invention is to provide an oil cushion beneath the valve stems which is positively regulated so as to prevent impacts between the valve head and the valve seat.

40 Still another object of this invention isto provide a mechanism in which the cam surfaces for operating the valves are kept in constant engagement so that no impact can occur at this point.

In the drawings:

Fig. l is a front view of a steam engineshowing the location of the valve control means of the invention. 1

Fig. 2 is an end view, of Fig. l. i

Fig. 3 is an enlarged sectional view taken on the line 3-3 of Fig. 1 and shows the position of the cams in the closed position of the valve.

Fig. 4 is a side view of Fig. 3. Another object of the invention is to provide e n 7 e sectiqnal views Similar to 45 a mechanism in which pivoted levers are elim 3; 5 Shows the 13051131011 of the m when inated so that a more compact and silent mechthe Valve is 1 6 ShOWSthB Position of the anism may be used. cams just prior to the closing of the valves; and 7 Another object of this invention is to provide 7 S O S the position of the cams While the 5m a, mean whereby the oil cushion beneath the oil is being released from beneath the valve stem.

Valve stem may be created under pressure and Fi is front V w O od fied o m Of he be released under a pressure which is so reginvention in which a centralized valve control ulated that the valve head may set quickly, yet mechanism is used. v quietly, upon the valve seat. Fig. 9 is a side view of Fig. 8. I l

;; \A further object of the invention is. to lift the Fig.- 10 isa view of the operating mechanisms 551' 7 legs.

' shaft 3 and shaft through duct H with cylinder 55. Pistons valve to its highest position by either cam 28 or cam for the valves showing the association of the elements enlarged from Figs. 8 and 9.

Fig. 11 is a plan view of the valve time setting mechanism of Fig. 1, and

Fig. 12 is a plan view of the arrangement of the control mechanism of Figs. 8 and 9 about a central cam.

As shown in Fig. 1, the invention isapplied to a steam engine having a conventional cylinder block A, a base B, and connecting legs C. The intake valves are shown at I and the exhaust valves are shown at 2, these valves being operated by cams mounted on a cam shaft 3. The oil cushioning mechanism is contained within housings denoted generally at D which envelop the base of the valve stems and the various piston chambers. Main cam shaft 3 is driven from the crank shaft 4 through intermediate geared connection indicated at 4 and consisting generally of bevel gears with interconnecting driving rods. The cam shaft 3 may be axially displaced by such means as a motor 5 mounted upon one endthereof so that the engine may be driven forwardly or ,ackwardly.

An auxiliary cam shaft ii is mounted adjacent and parallel to the main cam shaft 3. Spur wheels I and 'l' are mounted respectively upon 6, said wheels engaging each other to provide for a rotation of shaft 6 with shaft 3. Between wheel '5' and shaft 6 is mounted a tiltable bevel spur gear 3, this gear being tilt-I able by operation of a hand wheel 9 through geared connection it. Tilting of this wheel 3 causes the timing of the cam shaft 9 to be made either leading or trailing with respect to the position of the cam shaft 3.

The valve housings indicated generally at D surround cams mounted upon the cam shafts fl and 6, and each provides a housing for three piston cylinders, note Figs, 3 to 7. These piston cylinders are contained in the upper portion 42 of. the housing D and are shown at 13, M, and."

i5. Cylinder l3 communicates through duct 85 with cylinder l4, and cylinder 14 communicates it, 26, and 2! are mounted in these cylinders.

A valve stem is shown at l9, which valve stem is provided with a stop it and'terminates in pis ton l3 located in cylinder l3. Loosely surrounding the portion of the valve stem below the stop I9 is the top of a valve lifting member 22, whichmember is bifurcated below the stop so that the legs 22' pass by the chamber 13 andrest upon a cam 25 through a roller 24 connected by a wrist-pin 2 3 to the lower ends of the Ca m, 25 is mounted upon main cam shaft 3. The cam track of cam 25 is shown in Fig. 3 and 'is such, as may be seen by making a successive inspection of Figs. 3 to 7, as to raise the intake and then to drop the member 22 down to its lowest position (note Fig. 6), without drawing the valve down with it. The lowering of the member 2?. is caused by a spring 23 which bears upon the shoulder, 233'- of member 22, and consequently keeps the roller 24 in constant contact with the surface of cam 25.

A piston 28 is contained within cylinder M, the lower end of, which is connected to an inverted T- shaped member 26. At the inverted T are rollers 2'5 and 23, which roll.- ers, respectively, engage cams 29 on shaft 3, and 30 on auxiliary shaft 6. Therefore theposition of the piston 28 within cylinder M is determined 38. FromFig. 7-.it is the ends of the head of ciable impact between the rollers and the sur faces of the cams.

Piston 2! in cylinder is controlled from auxiliary cam shaft 6; by means of a piston rod which terminates in a roller 32 bearing upon cam 3i mounted upon auxiliary cam shaft 5.

Oil or other operating fluid is supplied to the various valve operating mechanisms shown in Fig. 1 from container 33 through tube 3% to the supply cylinder it. The fluid may be passed through the tube under atmospheric or under additional pressure.

The operation of this apparatus is as follows: The timing of the auxiliary cam shaft with respect to the main can: shaft is set by means of, the hand-operated wheel ii. With the intake valve closed, the positions of the cams and operating pistons are as shown in Fig. 3. Fluid fills the cylinder l4. As cam 25 rotates clock-wise (see Fig. 5) the intake valve is lifted by member 22 bearing against stop l9 on the valve stem, compressing spring 23, and raising piston is. Because of the pressure of the fluid coming from supply chamber 33, the fluid flows into cylinder l3 beneath piston l8. Upon further rotation of the cam the member '22 is dropped and is kept in contact with the cam by pressure from spring 23. At the same time, cam 29 has raised piston 20 through roller 21, and closes the outlet orifice of conduit I6.

Therefore, the valve stem cannot drop because of the oil contained in cylinder l3 beneath the piston l3. Also, at the same time, piston 29 has'been raised by the cam 3! moving counterclockwise on auxiliary cam shaft 6, and the fluid contained in cylinder l5 has been forced under pressure through the conduit ll back into the conduit 3% toward the supply chamber 33 (see Fig. 6). To allow the valve to drop, and utilizing the fluid contained in chamber l3 .as a cushion against the sudden dropping of the valve such as would cause an impact between the valve head and the valve seat, the conduit i6 is brought into communication with the conduit H by further upward movement of the piston which has a reduced central portion so as to allow communication therearound. Fluid then escapes from cylinder l3 through conduits id and l'i to cylinder l5, and the rate of escape of this fluid is controlled by the downward movement of the piston 2i as regulated-by the cam 3i. As soon as the valve has seated, pistonZll is lowered to its initial position as shown in Fig. 3.

It is to be noted that the action of the piston 2| gives a very good positive control of the rate of release of the fluid from beneath piston 58. It

is also noted that not only is the fluid used as a cushioning means, but that the lowering of the piston 25 causes the fluid to form a positive connection between the pistons l8 and 2! and enables a very close regulation to be made of the piston 58 by means of the piston 2i. While the valve may have a downward pressure on the fluid cushion by means of its own weight, such pressure may be increased by means of a spring, or, in a steam engine, by the steam pressure in the main steam cylinder.

The cylinder i3 is preferably surrounded by Furthermorait is noted that the'connection between the fluid supply chamber M and the supply container 33 is kept constantly open.

Therefore, any fluid which may leak past the pistons is immediately replaced and the timing of the valves is kept constant. 1

In the form of the invention illustratedin Figs. 1 through '7, a fluid supply cylinder and a fluid release cylinder is provided for each valve in the engine the two cylinders being contained within the same casing. It is possible, however, to remove the fluid release cylinder fromeach individual valve and to put a plurality of the fluid release cylinders around a single cam to be operated thereby. This structure is shown in Figs. 8 through 12, and has the advantage that a single main cam shaft may be used to operate the intake and exhaust valves of the engine, and a small auxiliary cam shaft can be located upon any portion of the engine, around which are mounted a plurality of fluid supply cylinders and a number of fluid release cylinders.

Then a first cam on the auxiliary shaft operates all the pistons in the fluid supply cylinders, and a second cam on the auxiliary shaft operates all the pistons in the fluid release cylinders.

' In Figs. 8, 9, and 10 the inlet valves are again shown at I and the exhaust valves at 2. In Fig.

8 each of the valves F and G is controlled by its individual cylinder 15 located adjacent auxiliary shaft 40. Four cylinders are shown for the four inlet valves 8 illustrated in Fig. 8. All of the cylinders I5 are connected by branch pipes to a common conduit 48 which in turn connects with reservoir A single conduit 45 connects all the valves l with reservoir 33 by means of branches. Further, two cylinders i5, are connected with a pair of valves, as the valves F and G, by means of a conduit 4! and branch conduits to the cylinders and valves. 1 Fig. 10 illustrates the construction of valve F and its corresponding cylinder i5. Valve stem i9 is connected with piston 58 mounted in cylinder It, as in Figs. 1 to '7. Located adjacent cylinder i3 is a first supply cylinder I ia. in which is mounted a supply piston 261a operated by cam 43 on main cam shaft 3 through roller Z'la. Cylinder Ma communicates with container 33 through branch 45a connected to conduit 45, a second branch @577 similarly serving valve. G. Cylinder Ma further communicates with cylinder it through tube 46, and still further communicates with a second supply cylinder ldb by means of conduit M and branch 41a. Another branch All; similarly serves valveGa Cylinder Mb communicates with container 33 through conduit 48 and branch 48a, the branch 48b likewise serving valveGr.

Supply cylinder Hibfurther communicates with fluidrelease chamber l5 through conduit 49. A piston 25 in cylinder I5 is operated through a roller 32 by cam 3i mounted upon auxiliary cam shaft 49. The piston 2th mountedin cylinder Mb is operated through roller 2% by a cam 44 mounted upon auxiliary cam shaft 40. As shown in Fig. 12, the four cylinders 55 are oper ated from thecams on the auxiliary cam shaft.

As sho-wnin Fig. 9, the setting of the auxiliary cam shaft with respect to the angular position of the main cam shaft may be accomplished from hand wheel 9 and connecting mechanism 42. The drive for the main cam shaftistaken oif from the main engine shaft by means of shaft which acts as a pinion for a bevel gear M used to drive the auxiliary cam shaft 40.

The operation of this embodiment of the invention is as follows: r i

The angular position of the auxiliary cam' shaft with respect to the main cam shaft is set by means of hand wheel 9. Fluid from container 33 fills supply cylinder. Ma and supply cylinder Mb through the conduits 45' and 48, respectively. As valve stem I9 is being lifted by means of elements 25, 24, 22, Hi, to its high-- est position, the piston 20a is also raised by cam 43 and the roller Zlwto its highest-position, at which point conduit 41,

41a communicates! through the space around the piston 20a with conduit it. The valve stem cannot drop because of the oil now containedin the conduits 46 and 4i. Isis to be noted thatyat this timejpiston' 2% in cylinder Mbis still in its lowest position as shown in Fig. l0. Therefore, piston 2|, when rising in cylinder !5, because of cam 3|, is ejecting fluid from cylinder 15 through conduits 49 and 48 back into supply container 33. Just after the piston 21 reaches its highest position, the

piston 20b is raised by cam 44' to connect the,

conduits 4'! and 49 and therewith the cylinders l8 and 15 through the conduits d6, 41a, 41 and 49.

ll, 49 into cylinder i5, and valve stem lS is lowered. The'rate of escape ofthe fluid is regu- Supply conduits t5 and 48 from container 33 ensure that the amount of fluid is kept con- .stant throughout the operation of the device,

and that no harm is done by loss of fluid through leakage. The fluid can be cooled by means of a cooling coil 50 connected to inlet 5| and out- The release of the fluid from cylinder i3 is accomplished by further rotation of the shaft Mi and cam 3! so that thepiston 2! moves down--. wardly- Therefore fluid below the piston 18 in cylinder it may escape through conduits 46, 41a,

la-ted y the position and downward movement of piston 2 AS in 1, the downwardpressure lets 52 and arranged intermediate the length of the tube 41. I

It is important to note that with respect to both of the forms of the invention described, the movement of the fluidtakes place in substantially one direction, that. is, it'can besaid' that fluid coming from the container33 is supplied to the cylinder 83, thento the cylinder 15,

and then back to the container 33. The setting of the valves is effectively and positively accomplished through hydraulic means, and a noiseless operation of the motor is ensured.

' Having described rriecl-lanisms by which I have 2. A valve control mechanism comprising a cam operated mechanical means for opening a achieved the objects of'my invention, what I j valve'and independent cam controlled hydraulic means for regulating thev closing of'said valve.

3.1% valve control mechanism comprising a valve having a valve stem, mechanical means for moving said stem to open said valve, means for placing a hydraulic medium behind saidstem for maintaining said valve in open position, meanspfor releasing said fluid medium, and means for positively controlling said releasing means.

as valve control mechanism comprising a valve having a valve stem, a cam, cam operated means to move said valve into open position,

means to inject a fluld medium beneath said stem, a second cam, and means operated by said second cam to regulate the release of said fluid medium from beneath said stem.

5. A mechanism for'operating valves comprising valves, main and auxiliary cam shafts, valve 3 lifting mechanisms operated by said main cam shaft for mechanically opening said valves, means for maintaining said mechanisms in contact with main shaft irrespective of the positions of said valves, hydraulic means for maintaining i saidvalves in open position, and hydraulic means a first piston joined to one end of said stem,

7 a cylinder for said piston, a second cylinder having a second piston therein, and a third cylindeihaving a third piston therein, means to supply fluid from a supply container to said second cylindena first conduit means between said first and second cylinders, a second conduit means between said second and third cylinders, means hearing against said stop to open said valve and to move said first piston, means to move said second piston to seal fluid beneath said first piston, and means to move said third piston to regulate the release of said fluid from beneath said first piston after further movement of said second piston to enable the release of said fluid.

8. An apparatus as in claim 7, said second:

piston having a reduced midsection to allow fluid passage therearound.

9. An apparatus as. in claim '7, said means bearing against said stop comprising a bifurcated member extending past said first cylinder, a main cam shaft having a cam thereon, and means for keeping said bifurcated member in constant contact with said cam irrespective of the position of said step.

10. An apparatus as in claim 7, a main cam shaft, and an auxiliary cam shaft, said means to move said second piston comprising an inverted T-shaped connecting rod movable by cams on either of said shafts.

11. An apparatus as in claim 7, a main cam shaft and an auxiliary cam shaft, a cam on said main cam shaft for operating said means to open said valve, said means to move said third piston comprising a cam on said auxiliary cam shaft,,and a connecting rod between said second cam and saidthird piston.

12. An apparatus as in claim '7, cooling means for said fluid.

13. An apparatus as in claim 5, a cam on said auxiliary cam shaft for operating a plurality of said regulating hydraulic means.

14. A valve cushioning apparatus comprising a valve stem, means for moving said valve stem, a first fluid supply cylinder having a first piston therein, means to move said first piston to allow fluid to pass beneath said stem, 2. second fluid supply cylinder having a second piston therein, a second means to move said second piston to allow fluid to pass to said first cylinder, and a third cylinder having a third piston therein, and

means to move said third piston to regulate therate of release of said fluid from beneath said stem.

15. In a valve mechanism a main cam shaft and an auxiliary cam shaft, mechanical means controlled by said main cam shaft to open valves, hydraulic means controlled by said 311K111 iary cam shaft to maintain said valves in open position and to regulate the closingof said valves, a main drive shaft, means to drive both of said camshafts from said drive shaft, and means to vary the angular displacement of said auxiliary cam shaft with respect to said main cam shaft.

' WILHELM RIEGER. 

